Carbon dioxide snow machine



June 21, 1932.. ZUMBRQ 1,864,398

CARBON DioxIDE snow MACHINE Filed. Jan. 19 1929 swam 1 :0?

Patented June 21, 1932 UNITED STATES PATENT orrlca FRANK B. ZUMBRO, OI WAYNESBORO, PENNSYLVANIA, ASSIGNOR TO ERICK COMPANY, 01 WAYNESIBORO, PENNSYLVANIA, A CORPORATION 01 PENNSYLVANIA cannon moxma snow 'amcmmr Application filed January 19, 1829. Serial No. 888,581.

This invention relates to method and means for making carbon dioxide snow or ice. An object of the invention is to provide an improved method and means for supply- 5 ing carbon dioxide to the compressing and cooling system of a carbon dioxide snow making system.

Another object is to provide a method and means for charging the system with the fluid from commercial drums without materially lowering the temperature of the fluid in the drums to cause moisture in it to freeze at the mouth of the drum.

A further object is to rovide a method and means for making car on dioxide snow and ice without subjecting it to the high pressures hitherto found'necessary.

A further general object is to increase the efliciency of snow making machines and to cheapen the process of making carbon dioxide snow and ice.

Other objects and advantages will become apparent as the invention is more fully disclosed in the description which follows. Referring to the accompanying drawing which is made a part hereof and on which similar reference characters indicate similar arts p The figure of the drawing shows the general arrangement of units in a carbon dioxide snow making system using my invention. In the drawing, numeral 10 indicates a first stage compressor unit having fluid inlet and outlet conduits 11 and 12. A scale trap 13 may be placed in the inletconduit 11 in advance of the compressor 10. The outlet 0011-. duit enters afluid mixing unit 14. Here the fluid from the compressor is mixed with cold gas which pames through a pipe 15 from the liquid coolers and 38 to be described later. The cooled mixture of ase's under the discharge pressure of the rst compressor unit passes from the mixing chamber through a pipe 16 toa second stage compressor unit 17. From this compressor the fluid passes through a pipe 18 to a cooling unit 19. This cooling unit may be cooled in any suitable wa such as by means of coils 20 through which cold water is circulated. This cooling unit also acts as an oil separator, the oil being deposited on the cold pipes and falling into the bottom of the shell from which it may be drawn off through valve 21.

From the cooler 19 the gas passes through a pipe 22 to an oil filter 23. This filter may be of any suitable construction, such for example, as that shown and described in my co-pendin application Serial N 0. 313,887, filed Octo er 20, 1928 for method and a paratus for manufacturing carbon dioxide ice from liquid carbon dioxide. From the filter the fluid passes through a line 24 to a condenser 25, thence through a pipe 26 to a receiver 27. From the receiver the fluid asses through a pipe28 which branches, one

ranch 29 entering the shell of a liquid cooler 30, the other branch 31 enters a coil or tubes 32 in the cooler. A valve 33 controls expansion of the gas from the line 31 into the coil or-tubes 32.

The liquid cooler 30 is of any suitable type in which the liquid being cooled is separated from the cooling medium by a heat transmitting surface, such, for example, as that shown in my co-pending pplication Ser. No. 333,559, filed January 9, 1929, for liquid coolers.

A valve 34 controls passage of fluid through the pipe 29. A line 35 leads from the line 28 and branches into pipes 36 and 37, the pipe 36 passing into the shell of a liquid cooler 38 and the pipe 37 passing into the coils or tubes 39 within the cooler. Under certain conditions it may be preferable to have the fluid to be cooled passthrough the tubes or coils in the cooler and have the cooling fluid tubes. Either method falls within the scope of my invention. The liquid coolers act both to cool and dry the carbon dioxide, the water content of the carbon dioxide freezing on the outside surfaces of the cold fluid conduits. Valves 40 and 41 control passage of fluid through pipes 36 and 37. The expanded fluid from coils or tubes 32 and 39 passes through pipes 42 and 43 to pipe 15 through which it enters into the mixing chamber 14. Cold liquid carbon dioxide passes from the occupy the space in the shell surrounding the coolers through pipes 44 and 45 to the snow machine 46 where it expands to form snow.

'coo ers 30 and 38, respectively.

Such of the expanded carbon dioxide as is not frozen passes through the line 47 to the intake of the first stage compressor 10, where it cools the gas entering the compressor. pi 48 passes from the line 24 to a pipe 49 w ich enters the top of each of the liquid coolers. Valves 50 and 51 control passage of as from the pipe 49 to the top of the A line 52 passes from the pipe 18 to the snow machine 46. The purpose of this last line is to deliver warm gas to the snow machine to thaw out the machine from time to time to remove ice which may have adhered to the side of the machine.

For supplying the system with carbon dioxide I mount drums 53 to headers 54 and 55. Valves 56 control the outlets of the drums. The other ends of the drums are connected to a line 57 controlled by valves 58. Headers 54 and are connected to a pipe 59 which connects to the pipe 11 passing to the intake of the first compressor unit. A branch 60 controlled by a valve 61 passes into the mixing chamber 14 in advance of the second stage compressor. Pipe 59 has a valve 68 controlling admission of fluid to the line 11. A valve 69 in pipe 47 controls passage of fluid from the snow machine to the compressor 10. Branches 62 and 63, controlled by valves 64 and 65 pass to lines 29 and 36 entering the liquid coolers 30 and 38.

In the drawing I have shown commercial carbon dioxide drums 53 mounted so as to allow the fluid to flow by gravity to the coolers. By mounting the drums in this way a liquid seal is maintained at the outlet at all times to prevent expansion from the surface of the fluid to cool the fluid and consequently to freeze the outlet from the drum. I may secure the same results by mounting the drums in an upright position and siphoning ofl the liquid from the drums by means of a tube which extends well down into the drums. Either of these methods is particularly desirable when the drums have water in the carbon dioxide. When there is water in the carbon dioxide this frequently freezes at the outlet of the drum, even when the drums are inverted as described above to provide a liquid seal at the outlet. By the method just described, the water in the drum which is heavier than carbon dioxide will remain at the bottom of the fluid, and hence will not pass off through the siphon tube, if the bottom of the tube be above the level of the water, and thus danger of freezing at the nozzle is avoided. Where found necessary the hot fluid line 57 may be opened to thaw any frozen water from the valve of the drum and aid in completly exhausting thedrums.

In starting the plant for the first time carbon dioxide may be charged into the system from the drums 53, either through lines 59 and 60 or 11, using valves 61 and 68 to conmosses pansion valves. The gas so drawn into the A system is compressed, cooled and condensedand passed into the receiver 27 and to the shell of the liquid cooler 30 through the valve 34 and line 29, but is prevented from passing to the liquid cooler 38 since the valve 40 is closed. Valves 66 and 67 being closed carbon dioxide fluid is allowed to completely fill the cooler 30. When a suflicient supply of carbon dioxide has been built up in the cooler 30 and receiver 27, valve 33 is slightly opened and fluid from the line 28 is allowed to expand through valve 33 into the coil or tube 32 which in evaporating cools the liquid in the shell of the cooler 30 to a temperature low enou h for its passage to the expansion valve of t e snow machine. When the liquid in the cooler 30 has been sufliciently cooled, the valve 34 is closed, thus cutting off this cooler from a further supply of carbon dioxide from the receiver 27. The pressure in the cooler is maintained by opening valve 50 to admit gas pressure from the line 48 to the top of the liquid in the cooler. The gas from the hot line 48 will act on the surface of the liquid carbon dioxide in the cooler. This hot gas will not materially affect the temperature of the liquid carbon dioxide in the cooler because of the fact that the liquid carbon dioxide is a very poor conductor of heat. Very little heat from the gas therefore will be transmitted to the cold surface of the liquid carbon dioxide.

After the liquid in the coolers is subjected to the pressure in the compressor system, the valve 66 is opened and the liquid allowed to pass to the expansion valve (not shown), of the snow machine. While the cooler 30 is being emptied fluid carbon dioxide from the drums is admitted to the cooler 38 as follows: The expansion valve 41 is slightly opened and fluid carbon dioxide is expanded into the coil or tube 39 to cool the shell 38. Carbon dioxide from the drums 53 is then admitted to the cooler by opening valve 65,

valves 61, 68, 40, 51 and 67 being closed. The

low temperature in the cooler 38 allows the pressure in the cooler to be quite low so that fluid flows readily from the drums to the cooler to fill it. It is evident therefore that by this process the fluid is cooled at the same time as it is being admitted into the cooler, and hence no energy is lost in passing the supply from the drums to the system. When the cooler 38 has been filled with carbon dioxide from the drums the valve 65 is closed and the valves 51 and 67 are opened and gas from line 48 subjects the surface of the fluid in the cooler to the pressure in the system to force the cold liquid carbon dioxide from the cooler to the snow machine. While the cooler 38 is being emptied the cooler 30 is being filled from the drums. As thebperamenace tion continues there may be an accumulation of liquid in the receiver, resulting from the condensation of the gases drawn from the snow machine. From time to time this liquid carbon dioxide may be admitted directly into the coolers. When the drums have been emptied of so much of the fluid as will pass into the coolers, valves 64 and 65 may be closed and valves 61 and 68, or either of these, may be opened to subject the drums to the suction of the compressors by means of which these drums are completely exhausted of their contents. p

In the drawing only two coolers have been shown, and the operation has been described as if these operated alternately. Of course, the system is not limited to the use of two coolers, as such a number may be used as will be found necessary in order to have a continuous expansion from one of the coolers to the snow machine, some of the coolers being filled and cooled while others are being emptied by expanding to the snow machine.

It will be obvious to those skilled in the art that various changes may be made in my device without departing from the spirit of the invention, and I, therefore, do not limit myself to what is shown in the drawing and described in the specification, but only as set forth in the appended claims.

Having thus fully described my said invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a snow making system having means for compressing, cooling and condensin carbon dioxide, a receiver for the condense carbon dioxide, a liquid cooler, means for delivering carbon dioxide from commercial drums to said cooler, means for expanding the said condensed carbon dioxide from the receiver to cool the carbon dioxide in the cooler and means for subjecting the liquid in the cooler to the pressure in the receiver, substantially as set forth.

2. In a snow making system having means for compressing, cooling and condensing carbon dioxide, a receiver for the condensed carbon dioxide, a plurality of coolers, means for delivering liquid carbon dioxide alternately to the coolers and means for expanding a portion of the said condensed carbon dioxide from the receiver to cool the carbon dioxide in the coolers, means for alternately subjecting the coolers to the pressure of the compressors, and means for alternately expanding the condensed carbon dioxide from the coolers to a snow machine, substantially as set forth.

3. In a snow making system a plurality of coolers for li uid carbon dioxide, means for filling some 0 the coolers with liquid carbon dioxide and cooling the same while other coolers are being evacuated of 'carbon dioxide, the means for evacuating the coolers comprising means for subjecting the coolers to a gas pressure which forces the li uid from coo ers to the pressure of the carbon dioxide.

from the compressors to force the liquid from the coolers to evacuate them, the filling and evacuating of the coolers being operated so that some are being filled while others are being emptied, substantially as set forth.

5. In a snow making system having means for compressing, cooling and condensing carbon dioxide, a receiver for the condensed carbon dioxide, a. liquid cooler, a plurality of carbon dioxide containers having means for delivering carbon dioxide therefrom to the said cooler, means for expanding a portion of the liquid carbon dioxide from the receiver to cool carbon dioxide in the said cooler, and means for drawing ofi' carbon dioxide in advance of the condenser and delivering itto the said cooler to subject the liquid therein to the pressure maintained in the system in advance of the condenser, substantially as set forth. I

6. In a snow making system having means for compressing, coolin and condensing carbon dioxide, a receiver or the condensed carbon dioxide, a plurality of liquid coolers, means for delivering carbon dioxide from containers in which it is stored to the coolers,

means for expanding liquid from the receiver to cool the carbon dioxide in the coolers, means for selectively subjecting the liquid in the coolers to the pressure maintained in the system just in advance of the condenser, and means for conducting the fluid which has been expanded to cool the coolers to the suction side of the compressors to increase the pressure of and to decrease the temperature of the gas in the compressor cylinder,

substantially as set forth.

7. In a snow making system having a first and a second stage compressor, means for cooling and condensing carbon dioxide, a receiver, a liquid cooler, means for supplying the coolers with carbon dioxide from commercial containers, means for expanding carbon dioxide liquid from the receiver to cool the liquid in the cooler, means for subjecting the surfaceof the liquid in the coolers to the high pressure side of the compressors, and means for conducting a portion of the fluid expanded from said containers to the intake of a first stage compressor and a portion to the intake of the second stage compressor, substantially as set forth.

8. In a snow making system havin a series of compressors and means for coo mg and condensing carbon dioxide, a liquid receiver, a plurality of liquid coolers, means for selectively filling the coolers with liquid carbon dioxide, means for cooling liquid carbon dioxide in the coolers to reduce its temperature and its vapor pressure so that carbon dioxide at higher temperature than vapor pressure may easily be delivered into the said coolers, means for disconnecting the said coolers with the source of sup 1y of liquid carbon dioxide, and means or supplying pressure to the said coolers to force the liquid from the coolers to evacuate them, and means connected to the liquid cooler for delivering the cool liquid carbon dioxide to a snow machine, substantially as set forth.

In witness whereof, I have hereunto set my hand and seal at Waynesboro, Pennsylrania this 16th day of January, A. D. 1929:

FRANK R. ZUMBRO. 

